hi, i have kubuntu amd64 12.10 and virtualbox works with a kernel 3.5.0.
i have download kernel 3.9.0-rc4 from kernel.org

make-kpkg --rootcmd fakeroot --initrd kernel_image kernel_headers modules_image

but after installation virtualbox write

WARNING: The character device /dev/vboxdrv does not exist.
Please install the virtualbox-ose-dkms package and the appropriate
headers, most likely linux-headers-.

You will not be able to start VMs until this problem is fixed.
how fix this thanks.